Method and apparatus useful in repairing wells



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Film Oct.. 21. 1942 Dec. 26, l1944.

METHD AND APPARATUS USEFUL IN REPAI'RING wELLs WZ/Wey Patented Dec. ze, 1944 METHOD AND APPARATUS USEFUL IN nEPAmmG WELLS l Arthur L. Armement and melma A. wens,

' Long; Beach, Calif.

Application october 21, 1942, sei-lai No. 462.314

(ci. lsv-,17)

Claims.

'This invention relates to the art of oil wells, gas wells, etc. and relates more particularly to a method and apparatus useful in reparing tubing, casing. etc. of such wells. A general object of this invention is to Provide a rapid, efficacious ,i

method and a simple, practical and inexpensive apparatus useful in repairing leaking well casing and tubing.

Leaks often develop in the casing and tubing of producing wells. For example, where a well is producing from spaced strata separated by a packer on the tubing or ow string, and the uid from a lower stratum is independently conducted to the ground surface through an inner string of tubing, leaks frequently develop in the inner string and allow the fluids fromthe Ntwo strata to commingle. The fluid from the upper productive stratum ows through the yliner of the outer casing with substantial velocity and impinges against the inner string and this -impinging fluid usually carries solid matter which abrades the inner string and iinally cuts holes in the 4same to'permit the commingling of. the 'fluids from the separate strata.

Before such leaks can be repaired it is necessary to ascertain their depth or position Awith a reasonable degree of accuracy and it is'difllcult to accurately rdetermine the position of such leaks. locate the leaks, uid from the earth formation was allowed or caused to flow into the well in quantities and in substantial velocities with the result that the well sanded up or received a large volumeof solid matter which later had to be removed from the well at great cost,

Another object of this invention is to provide a method for locating leaks in well casing, tubing, etc. that does not result in the passage or entrance of solid matter into the well. In accordance with the method of the present inl vention clean iiuid is employed and the Well does not receive any solid matter but is actually flushed or cleaned as aresult of the method.

Another object voi this-invention is to provide a method of the character mentioned in which the depth or position of the leak may be determined with great accuracy.

Another object of this invention is to pro' vide a method for locating leaks in well casing,

well tubing, etc. that may be quickly carried out without disturbing or interfering with the casing. tubing, or otherpermanent parts of the well installation.

Another lobject of this invention is to 'pro- In the methods heretofore employed to.

v in wells equipped in different ways.

may be effectivelyemployedpto successively locate a plurality'of leaks in the well tubing or string.

1 A further, object of this invention is to provide an apparatus of the character mentioned that may be readily employed and that is wholly withdrawn from the well at the termination of the operation. y

The various objects and features of our invention will be fully understood from the fol-y lowing detailed description of a typical preferred form' and`manner of carrying out our invention. throughout which description reference is made to the accompanying drawing, in which:

vThe ligure is a vertical sectional view of a well equipped for production from two spaced strata showing the apparatus of the invention in use to locate a leak in one of the well strings.

The method and apparatus of the present invention may be used in diierent situations and In thev following detailed disclosure we will ,describe the invention as employed in a well equipped to simultaneously produce froma plurality of.

separate, distinct strata, `it being understood that this is merely a typical illustrative application of the invention and is not to be construed as limiting or restricting the scope of the invention.

The'well W illustrated in the drawing passes through twovertically spaced productive zones or strata A and B. The well W is provided with an outer casing I0 which may be termed a vcombination casing'. The major upper portion of the casing Ill is imperforate, while the lower portion of the casing I0 which passes through the productive zone A is perforate, being in the form of a perforated linei` II. A shoe I2 is provided on the lower end of the casing I0 and is cemented in the well to provide a seal about the lower vand of the combination casing. The casing I8 extends to the ground surface where it is provided with'a head I3. The head I3 has one or more outlet conduits or pipes I4. An inner tubing or string I 5 i/s/provided to conduct or carry away the fluid/from the lower productlve stratumB. The string I5 is a combination string having a perfoate portion or liner I8 extending through the productive zone B, while the remaining portion of the string -I5 is imperforate. The liner I6 is provided at its lower end -with a shoe I'I and the'liner is perforatedto revide a method of the character referred to that 65 ceive the uid from the stratum B. 'I'he string l5 Passes upwardly through the casing or string,

y 25 known or determined plug 23 is run into the string I5 and set in the usual manner well known to those skilled in ,the

art. It is preferred to position and set the plug 23 at a point below all possible holes or leaks in the 'wall of the string I5. In practice the plug 23 may be set in the lower end portion of the string I immediately above its liner I6 so that `it will be below all possible leakage openings.

The string on which the plug 23 is run into the well is removed following the setting of the plug.

Following the setting of the plug 23 the sealing means 25 is secured to the lower section of string 24 and is introduced into the tubing string I5. 'Ihe h'ead I8 or its packing means 21 is assembled about the string 24 to provide a. seal about the 'string so that iluid under pressure may be circulated through the tubing string I5 without leakage fromthe head. In accordance with the inventionV the sealing means 25 is slowly moved longitudinally through the tubing string I5 while The sealing means may either be moved upwardly or downwardly through the tub- -'ing string I5. In the case illustrated it may be assumed that the sealing means 25 is to be moved upwardly through the ytubing string' I5 to locate o the points of leakage. In this instance the string 24 is assembled and run into the well `to bring the sealing means 25 to its lowest position. The lengths of the stands or sectionsY employed in making up the string 24 are determined and recorded as the string is run into the well sothat and then pass upwardly through the outer string I5 or then dissipate itself in the earth formation. Thus, in thel case illustrated, the fluid is pumped or forced through the pipe I9 to DaSS down through the lstring I5, out through the leak- .age opening or openings X and then upwardly through the outer string I0 to discharge from the pipe I4. It is preferred to deliver the iluid under substantial pressure, say a pressure oi 1000 pounds per square inch. The volume of fluid thus circulated through the strings` I 5 and I0, of course, depends upon the size of the leak or leaks X. The pressure on the fluid circulated may be indicated by a' pressure gauge 40 and the volume or quantity of fluid being circulated may be indicated by a gauge or meter 4I associated with the pipe I9 or with the pump or othermeans' delivering the fluid under pressure to the string I5.

With the initial position ofthe sealing means and with th e l'luid being circulated through the string lI5 under pressure, as above described, the string 24 is moved to slowly move the sealing' means 25 longitudinally through the tubing string l5. Where. th initial position of the'sealing means is in the lower portion of the string I5 below the zone of possible leakage the string 24 is moved upwardly to slowly raise the sealing means through the tubing string. So long as the' sealing means 2,5 moves through Il uid tight-imperforate portions of the string I5 y the pressure and thevolume of theuid beine iluid under pressure is circulated through the string.

exact position and extent of the leak X. will disclose circulated remain constant. However, when the sealing means 25 reaches and covers a leak X there is a reduction in the volume of theiluid being circulated through the string I5 and an vincrease in the pressure on the iluid. These changes are indicated by the gauge 4 0 and meter 4I. When the operator observes such changes in the readings of the gauge 40 and meter 4I movement of the string 24 is stopped and the position of the sealing means 25 is determined and noted. The depth'or position of the sealing means 25 may be readily determined by measuring the length or amount of the string 24 that has been withdrawn or moved upwardly during the upward movement of the sealing means 25. In the drawing it will be seen how the sealing means 25 may assume a position whereits sealing members 3i lseal with the wall of the string I5 at points above and below a leak X. With the sealing means 25 in such afposition the fluid being pumped or circulated into the string I5 cannot reach the leak X thus covered and there is, as a result, an increase in the pressure of the uid and a reduction in the volume of the iluid circulated. The sealing means 25 may be shifted slightly to ascertain the The gauge 40 and meter 4I whether there are any additional openings or leaks in the string I5. For example, if the pressure gauge 40 and the meter 4I indicate that there is a substantial volume of fluid in circulation when the sealing means 25 covers the known or located leak X there is in all probability an additional leak or leaks above the leak that has been located. In this situation the string 24 is again moved to slowly advance the sealing means 25 through the string I5.l It will be seenV that when the sealing means 25 is raised or moved from the located leak X that the fluid is free to pass through the openings 30 and tubular body 28 to by-pass the sealing means 25 and l thus the uidis free to again escape through the located leak X. The pressure and the volume of the circulated uid is thus returnedv to,

the normal or original values. The sealing means 25 is moved slowly upward through the string l5 until it Acovers the second or next leakl X. When this occurs the gauge 40 and meter 4I again indicate that the pressure on the fluidhas increased and that the volume of iiuid circulated has decreased and the operator stops movement of the string 24 and ascertalns the Q position of the newly encountered leak X by measuring or determining the length of the string 24 that has been raised from the well. By

repeating the above described operations all oi' several spaced leakage openings in the string l5 may be accurately located.

When the leakage opening or openings X have i been located and their positions noted, as above described, the circulation of the iluid is terminated and the string 24 carrying the sealing4 means 25 is removed from the well. .The 'plug 23 is released and pulled Afrom the well. Appropriate steps are then taken to close or seal the leak or leaks X in the string I5. Theserepair operations are materially expedited by reason of the fact that the exact, locations o1' the leaks have beenaccurately determined. l \Having 'described only a typical preferred form and method of carrying out our invention, we do not wish to be limited or restricted to the specic e `details herein set forth, but wish to reserve4 to ourselves any variations or modifications thatl -4' assegni.

may appear to those shined in the art and rau within' the scope o! the following claims:

Having described our invention, we claim:

l. The method of locating a leak in. adtubular .well string which includes passing uid down- 3 Y wardly through said stringto pass .through the leak, moving a sealing means'through said string while the iluid is owing therethrough until the sealing means closesthe leak to reduce or terminate said now or uuic Aand determining the 1 position o! the sealing means in the well string.

2. The method of locating a leak in a -tubular well string which includes .passing iiuid downwardly through said string to pass through the leak, moving a sealing means through said string l5 while said iiuid is owing therethrough until the sealing means fromthe. string. t

3. The method o! locating a leak in a tubular .well string which includes closing the string below the zone of leakage,.i'o`rcing fluid under pressure downwardly through said string to pass out 25 through the leak, moving a-sealing means longitudinally through saidr string, while the iiow or said uid is maintained, until the sealing means closes the leak to restrict or stop the owt 6. 'lfhemethodot'locatingaleakinatubular well string which includes closing oi! the tubnhr stringbelowthesoneoileakagebyinstalllnga pluginthetubularstrlngclrculatinguidundr pressure through the tubular string by Dumm iiuiddownthroughthetubularstrlngrromits upperendtodischargefromtheleaktherein.' n moving a sealing means longitudinally through'.

the tubular string, on an operating string whose length is known, determining when the sealing means closes or restricts the leak by observing an increase in the pressure onithe uid being delivered to the tubular string, ascertaining the i position of the sealing means when such increase in pressure occurs by measuring the length oi the operating string, and then removing the operating means and sealing means iromthe well. A f' 7. Apparatus useful in locating a. leak in a tubular well string comprising, a plug for clos ing the well string at a point below thel leak, an operating string, a body on the operating string including a sealing member for sealing with the interior of the tubular string and operable -longitudinally in the tubular well string by the op- 8. Apparatus useful in locating a leak in a tubular well string comprising, a plug for closing or uuid through the string. ascertaining the po- :to the weii string et e point below the leak, an opsition of the sealing means when it closes or restricts kthe leak, and then withdrawing the sealing means from the well. i

4. The method of locating a leak in a tubular erating string. a body on the operating string. and spaced sealing members on the body for slidably sealing `with the interior of the tubular body, the body having a passage for communiwell, string which includes setting a plug in the 35 eating with theA interior of the tubular string string below the zone of leakage. pumping fluid under pressure down the string to discharge into the string until said -means closes odthe leak,- ascertaining the position of said means o when 'it closes of! the leak, and then withdrawj u ing said means from the well.

under pressure through the tubular string by 50 such flow, operating a member in the string operabove and belowtthe sealing members.

`seals with the interior of the string longitudinally 40 ward through the string to escape through the 1 through the 1string while the uid is being pumped leak, moving a sealing means through the string,

while the iluid is owing therethrough until the sealing means closes the leak to reduce or terminate the'ow ot iiuid, and determining the posi- 45 tion ofthe sealing means .in the string.

10.v 'I'he method ot locating a leak in a tubularl well string which includes .establishing 'circulation ot duid through the string so there isy now-through the leak, observing thecharacter oi pumping uid down through the tubular string able to interfere with ow through the leak upon from its upper end to discharge from the leak therein, moving a sealing means longitudinally.

through the vtubular string, on an operating string whose 1engtn is known, determining when 5 the sealing means closes 'or-restricts the leak by observing a reduction in the circulation of the iluid, determining the position o! the -sealing means/when such reduction occurs by ascertaining the length or theoperating string, and then '60 withdrawing the sealing means, operating 'string and plug from the well.

reaching the location of the leak, observing the variation in the character of flow occurring when n' AnsiEN'moU'r. 1 :uomini: a wears.

when variation in the ilow 

